The general purpose and intent of this project is to conduct tests, research, and experiments directed toward the use and improvement of clinical procedures for measuring functions or properties relating to vision and the eyes. This includes subjective measurements of visibility and chromaticity thresholds and electrophysiological (objective) measurements as in electroretinography and electro-oculography, and physical measurements such as curvature, hardness, elasticity, and transparency. The loose definition of this project permits a degree of freedom which has been advantageous to other workers and projects in utilizing certain types of expertise, instruments, and materials.